Password Protect PDF
Lock a PDF with a password and AES encryption, and block printing or copying if you want.
Select a PDF fileor drop it anywhere on this page, or paste
Opens in your browser. Nothing is uploaded.
Password Protect PDF, free and private
Password protect a PDF so only people who know the password can open it. Do it before you email a payslip, share a signed contract or put bank statements in a shared drive. The file is encrypted with AES-256, the strongest method the PDF standard defines, and you can also block printing and copying.
Encryption runs in your browser with qpdf compiled to WebAssembly. The PDF and the password are never uploaded, and PDFToolz keeps no copy of either.
How to password protect a PDF
- 1
Select your PDF
Press Select PDF files or drop the document on the page. The tool protects one PDF at a time.
- 2
Set a password
Type it in the Password field, then again under Confirm password. It is used exactly as typed, spaces included. A meter shows how strong it is. Save the password somewhere safe.
- 3
Block printing or copying, if you want
Under Permissions, turn off Allow printing, Allow copying or both. Leave them on to give anyone with the password full access.
- 4
Encrypt and download
Press Protect PDF, then Download PDF. The file ends in -locked.pdf. Open it once to check the password. Your original file is not changed.
Why use PDFToolz for this
AES-256 encryption
Page content, images, and properties such as title and author are encrypted, not hidden behind a flag. Without the password, a PDF reader cannot show them.
Optional print and copy limits
Turning off printing or copying sets a separate random permissions password that nobody is told, so opening the file with the open password does not lift the limits in a PDF reader.
File and password stay local
Encryption runs in WebAssembly in your browser. Neither the document nor the password leaves your device.
Content unchanged
Only an encryption layer is added. Once opened with the password, text, fonts, images and layout match the original.
What the PDF password protects
This tool sets an open password, also called a user password. Anyone without it cannot open the file at all. With no permissions turned on, the same password is also the permissions (owner) password, so anyone who can open the file can print and copy it.
Encryption covers what is inside the file. The file name stays visible wherever the file is stored or attached, so keep sensitive details out of the name. Modern PDF readers support AES-256. A very old or basic viewer may not open the file.
Blocking printing and copying
Turning off printing or copying writes permission flags into the encrypted file. Adobe Acrobat, browser viewers and most phone apps respect them and grey out Print or Copy.
These limits are a request, not a lock. Some viewers ignore permission flags. Tools that decrypt the file, including Unlock PDF, can remove them with the open password. Anyone can also take a screenshot. Use them to discourage casual copying, not to protect secrets. The open password is what keeps out people who should not read the file.
Choosing a strong password
Encryption is only as strong as the password. Software can try many guesses against a copy of the file, and once the file is shared you cannot change its password.
- Use a long passphrase of several unrelated words, not a short word with a number on the end.
- Don't reuse a password from your email or bank.
- Send the password by a different route from the file, such as a text message or phone call.
- Spaces count. A space at the start or end becomes part of the password, so avoid them.
- There is no recovery. If you lose the password, the protected copy cannot be opened. Keep the original somewhere secure.
Changing a password and other tools
To change the password on a protected file, remove the old one with Unlock PDF, which needs the current password. Then protect the unlocked copy with the new one. Protect PDF stops with a message if the file already needs a password to open.
A file that opens freely but already has print or copy limits can be protected directly. The old limits are replaced by your new settings.
A password controls who can open the file, not what is in it. Before sharing, you can clear author and software details with PDF Metadata and remove sensitive passages for good with Redact PDF.
Frequently asked questions
Add the PDF, type and confirm a password and press Protect PDF. It is free, and the file and password stay on your device.
AES-256, the strongest standard method in the PDF specification.
Yes, in viewers that respect PDF permissions. Turn off Allow printing or Allow copying under Permissions. Some apps ignore these flags, and nothing stops a screenshot, so don't rely on them for secrets.
The protected copy cannot be opened, and PDFToolz cannot recover it because the password is never stored. Keep your original file or a note of the password.
Yes. If you know it, Unlock PDF removes it and gives you an unprotected copy.
Last reviewed . See how we build and test our tools, or report an error.
